The present invention relates to a sheet alignment apparatus for aligning a sheet-shaped sheet and to a sheet post-processing apparatus having therein the sheet alignment apparatus.
In many cases, a high-speed image forming apparatus such as an electrophotographic image forming apparatus is used in combination with a sheet post-processing apparatus that conducts post-processing including stapling, punching, folding and shifting on a sheet on which an image has been formed, and it is common that a sheet post-processing apparatus is equipped with a sheet stacking device that stacks plural sheets to form a bundle of sheets.
Many sheet stacking devices need functions to stack sheets by aligning edges of sheets which are fed in on a one sheet-by one sheet basis or on a several sheets by several sheets basis, in every direction, and-they are equipped with sheet alignment apparatuses each aligning a sheet edge in the vertical direction, namely, in the conveyance direction of a sheet to be fed in.
As described in Patent Document 1, for example, the sheet alignment apparatus has therein an alignment member that reciprocates in the direction crossing the conveyance direction in the case of feeding a sheet into the sheet stacking-device, to align the side edge of the sheet, and a stopper that is hit by a leading edge of the sheet when it is fed in, whereby, sheets which slide down along the inclined support member are aligned in every direction.
(Patent Document 1) Non-examined Publication Application No. 10-297815